Anti-friction disk for strip material cartridge

ABSTRACT

An anti-friction disk for a motion picture film cartridge includes an elongated, cylindrical central hub portion with a metal ring at the outer edge. The metal ring adds rigidity to the cylindrical hub portion so that the hub serves more effectively to keep a film roll in a generally round configuration, thereby avoiding crushing of the film supply or cinching of the film roll on the supply post.

[111 3,756,535 [451 Sept. 4, 1973 ANTI-FRICTION DISK FOR STRIP MATERIALCARTRIDGE [75] Inventor: Stephen H. Miller, Rochester, NY.

[73] Assignee: Eastman Kodak Company,

Rochester, NY.

22 Filed: Nov. 17,1971

211 App]. No.: 199,681

912,564 2/1909 Hastings 242/1 18.31

Primary Examiner-Leonard D. Christian AttrneyW. H. J. Kline et al.

[5 7 ABSTRACT An anti-friction disk for a motion picture film cartridge[52] US. Cl. 242/197, 242/71.8 A includes an elongated, cylindricalcentral hub portion [51] Int- C 1365b 5/ G031) G1 1b /32 with a metalring at the outer edge. The metal ring adds [58] Field of Search242/5519 A, 55.21, i idity to the cylindrical hub portion so that thehub 1 serves more effectively to keep a film roll in a generally 73round configuration, thereby avoiding crushing of the film supply orcinching of the film roll on the supply [56] References Cited post.

UNITED STATES PATENTS 3,208,685 9/1965 Edwards et al. 242/194 5 Claims,2 Drawing Figures I470 I63 x 36 7 Y- t V 7 7 2 9 Io WWII, l ,,V |iu 1 u'||n-"W -"l \J 7} lglllm illi fi lflllll fl 5 ill;m li it:[fil |Imin"liiflullllllnmmlhu R 5a tl llmnll |lll l illllllll l T" l v,'ll'w'llll llllllllimlllllllll l l lll llllllll,lilllml'llllllllllul!!!llll||l!lllll|n!!..,

PATENTEDSEP 4 ma STEPHEN H. MILLER INVENTOR.

ATTORNEYS ANTI-FRICTION DISK FOR STRIP MATERIAL CARTRIDGE BACKGROUND OFTHE INVENTION 3,208,685 issued Sept. 28, 1965, to Edwards et al. In

such a cartridge, film in a coreless coil or roll is positioned in thesupply chamber of the cartridge and is freely rotatable about the supplypost or central hub located therein. During operation of the cartridgein a camera, the film moves along a predetermined path through thecartridge, the path leading from the supply chamber, past an exposureaperture and into a film take-up chamber. Movement of film in thecartridge in any manner other than along the desired, predetermined pathcan be detrimental to the operation of the cartridge.

Films having a relatively thin base or overall web thickness have beendeveloped in recent years. Attempts t0 use such thinner and highlyflexible films in film cartridges have resulted in problems with filmmovement not anticipated by the prior art. When the thinner and moreflexible films are wound into a coreless coil or roll and placed in acartridge such as dis closed in the before-mentioned patent to Edwardset al, the convolutions of the film tend to collapse. Also, impactforces tend to cause distortion of the roll of film and cause the rollto collapse radially inwardly and bulge radially outwardly so that itassumes a generally elliptical shape. Such movement or collapsing offilm can result in the film cinching upon the supply post in the supplychamber or result in passage of the film into open areas of thecartridge. If the film were allowed to freely collapse or otherwise moveabout the cartridge in such a manner, excessive frictional forces couldresult, thereby causing unsteady film registration in the exposureaperture or otherwise causing erratic operation of the cartridge orcamera which receives the cartridge.

Many features typically used in a film cartridge serve to effectivelycontrol most of the movement of thin base film in the cartridge.However, those features do not adequately prevent the collapse of theinner convolutions of the supply roll and the related problems causedthereby. A brief explanation of the alternatives which have previouslybeen used for controlling the inner convolutions of the supply roll willillustrate the ineffectiveness of the prior art for controlling thinnerand more flexible films.

A first alternativefor controlling the inner convolution of the supplyroll was suggested by the aforementioned commonly assigned Edwards et alpatent. The Edwards et al patent generally disclosed an anti-frictiondisk which serves to confine the outer convolutions of a supply roll toa fixed diameter so those convolutions do not clockspring," i.e.,displace radially outwardly, into contact with the walls of the supplychamber. Also, the Edwards et al. patent discloses a lip extending fromthe inner portion of the anit-friction disk to prevent the innerconvolutions from collapsing or otherwise contacting the supply post inthe supply chamber. Though adequate for preventing the innerconvolutions of a roll of thicker base film from being displaced,experience has indicated that thin base films can collapse over such alip and contact the supply post. Additionally, the inner lip asdisclosed by the Edwards et al patent was supported by the supply postabout which the disk rotated. In at least one cartridge now commerciallyavailable from the assignee of the present invention, the supply post inthe cartridge includes a cut-away portion in the area where the postnormally would support the lip. A cartridge of this construction isdisclosed in commonly assigned copending US. Pat. application Ser. No.24,077, entitled Integral Anti-Backup Mechanism in a Motion Picture FilmCartridge, filed Mar. 31, 1970, in the name of Sutliff et al. Withoutsupport being given by the supply post to any portion of the lipexisting in the area of the cut-away, the film can deflect the lip uponimpact, thereby allowing the film to pass over the lip and collapsearound the supply post. Any film passing over the lip in this mannerwould then be free to pass into the open cut-away area of the supplypost and become compacted therein.

The aforementioned Edwards et al patent also suggests controlling of theinner convolution of a supply roll by inserting a pre-shaped tongue onthe inner end of the supply roll into a hole in the film spacedtherefrom to form a loop of film slightly larger in diameter than thepost. Such a loop is effective when used with thicker base films toprevent the inner convolution from decreasing in diameter beyond aminimum dimension and thereby cinching upon the supply post. Withconventional, relatively thick base films, the loop aids in preventingthe inner convolutions of the roll from collapsing. On the other hand,with thinner films, such a loop does not adequately prevent the filmroll from collapsing and cinching on the post. This is because thin basefilms are so limp that, when formed in a loop of the nature described,the loop will not support the outer convolutions wound upon it and anycoil thus wound is readily deformed by impact forces. In addition, theformation of the loop adds expense to equipment designed to spool filminto rolls. Thus it is desirable that any improvement directed atpreventing the inner convolutions from collapsing also should providefor the elimination of such a loop.

A third alternative, also suggested by the Edwards et al patent, is thatthe supply post or base could include a freely rotatable member uponwhich the innermost convolutions offilm may cinch. While thisalternative is a viable one for supporting thin'base films, theadditional costs for manufacturing and inserting such members in theassembled cartridges and the additional inventory required for suchmembers reduces the desirability of using this alternative.

It is apparent that an improved, less costly alternative is desired foruse in cartridges to prevent thinner and more flexible films fromcollapsing in the cartridge or otherwise passing into open areas of thecartridge. The subject invention provides such an alternative forachieving that objective with a resulting'reduction in manufacturinginventory and costs.

SUMMARY OF THE INVENTION An object of this invention is to provide afilm cartridge for cinematographic apparatus which will permit even veryflexible films to be readily withdrawn from the supply chamber.

Another object of this invention is to provide an improved anit-frictionmeans for minimizing the forces opposing the unwinding of a very thin,highly flexible strip from a supply roll.

Another object of this invention is to provide a film cartridge forcinematographic apparatus with means for preventing the innerconvolution of a supply roll of film from collapsing inwardly andcinching on part of the cartridge, even if the cartridge is subjected toimpact forces.

A further object is to eliminate certain manufacturing operations andtheir costs, such as shaping of the inner end of the film into a tongueand insertion of the tongue into a hole to form a loop of film.

Still another object of this invention is to provide a film cartridgefor cinematographic apparatus which prevents inward collapsing orcinching of even highly flexible film rolls and also prevents the outerconvolutions of the rolls of film from clockspringing into contact withthe peripheral walls of the supply chamber.

According to a preferred embodiment of the invention, a rotatable meansis provided for a film cartridge to reduce the forces opposing themovement of film from the supply roll within the cartridge, therotatable means further comprising a hub portion having a reinforcingrim to prevent collapsing of hub when impacted by the roll of film.

The invention, and its objects and advantages, will become more apparentin the detailed description of the preferred embodiment presented below.

BRIEF DESCRIPTION OF THE DRAWINGS In the detailed description of thepreferred embodiment of the invention presented below, reference is madeto the accompanying drawings in which:

FIG. 1 is a sectional view through a film cartridge according to apreferred embodiment of the present invention and showing the filmsupply side of the cartridge with certain parts broken away to bettershow the invention; and

FIG. 2 is an exploded perspective view of portions of a film cartridgeshowing a stationary supply post and an anti-friction disk constructedin accordance with the preferred embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Because photographic apparatusare well known, the present description will be directed in particuar toelements forming part of, or cooperating more directly with, the presentinvention, elements that are not specifically shown or described hereinbeing understood to be selectable from those known in the art.

Briefly, the present invention relates to a cartridge with ananti-friction disk of the type generally disclosed in US. Pat. No.3,208,685 to Edwards et al. The cartridge disk of this invention has acentral hub portion that serves to retain the innermost convolutions ofa supply roll of film at a minimum diameter, thereby preventing the filmfrom collapsing around the stationary supply post or boss about whichthe roll of film rotates and also preventing the film from otherwiseunnecessarily contacting other internal surfaces' of the cartridge.

As previously indicated, the present invention relates to certainmodifications and improvements to film cartridge disks of the typedisclosed in the aforementioned Edwards et al patent. Accordingly, thecomplete disclosures in that patent are incorporated herein byreference. In the following disclosure, numerals less than are used toidentify the same or similar parts disclosed in the Edwards et al patentand the numerals greater than 100 are used to identify features notdisclosed therein.

Referring now to the drawings, FIG. 1 shows a film cartridge generallydesignated 10 comprising a body 12 and a cover 14. Body 12 includes acylindrical film supply chamber 28 and a cylindrical take-up chamberpartially shown at 30 separated by a wall 32. The chambers are atopposite sides of the body substantially in coaxially alignment witheach other. A stationary locating boss or post 36 is formed integralwith wall 32 substantially at its center and projects into supplychamber 28. Boss 36 has a generally cylindrical bearing surface portion162 projecting from wall 32 and a frustoconical end portion 163 whichtapers radially inwardly from portion 162 toward cover 14. An opening164 in the boss extends through portions 162 and 163 as disclosed in thebefore-mentioned US. Pat. application Ser. No. 24,077. Boss 36 and thesupply and take-up chamber all have a common axis X.

In accordance with the present invention, a flexible, substantiallyannular, anti-friction disk 38 is provided. Disk 38 comprises a flattray portion 40, a lip 42 extending substantially perpendicular to theplane of and around the outer circumference of tray portion 40, and anoutwardly turned rim 43. The inner periphery of disk 38 comprises anintegral, substantially cylindrical hub portion and a rim portion 147.The hub portion 145 is substantially perpendicular to tray portion 40and projects from the same side of the tray portion as lip 42. Hubportion 145 projects from the tray portion by a distance substantiallyequal to, and preferably only slightly less than, the width of the filmroll 44 to be placed in the supply chamber. Rim 147 projects radiallyinwardly from the end of the cylindrical hub portion 145 opposite fromtray 40. The inner diameter of the rim is smaller than the diameter ofbearing surface 162 of the boss but is larger than the portion 163 ofthe boss that is located between the rim and axis X.

Disk 38 is coaxially positioned over boss 36 for rotation thereabout ina plane substantially perpendicular to the axis X of boss 36. Disk 38 issupported in this position by bearing surface 162 on boss 36 which isslidably contacted by the portion of hub 145 nearest the tray portion40. As is apparent from FIG. 1, this leaves the rim portion 147 and thepart of the hub 145 remote from the tray portion 40 unsupported bybearing surface 162. Because rim 147 is not supported by boss 36, and inviewof the tendency of rolls of relatively thin, highly flexible filmsto collapse or cinch around the boss 36, rim 147 is substantially rigidso that it supports the film roll.

The rim 147 can be made rigid by suitable reinforcing means, and in thepreferred embodiment illustrated the reinforcing means comprises a.metal ring 147a approximately 0.015 inches thick. The ring 147a can bevacuum formed into the anti-friction disk so that it is, in effect, anintegral part thereof. Alternatively the disk 38 and ring 147a can beseparately formed and assembled by pressing the ring into a seat in thecylindrical hub 145. Rim 147 is sufficiently rigid to support corelessfilm supply 44 and prevent the inner convolutions from deflecting orcollapsing the hub 145 upon impact. This also prevents the film frompassing over or from cinching upon boss 36 and from collapsing intoopening 164. It should be noted that disk 38 is purposefully very thinand quite flexible except in the area of rim 147, and that the rim 147together with the portion of the hub 145 positioned over surface 162provides good firm support for the film roll throughout its width.

A coreless roll or coil 44 of film is placed in supply chamber 28coaxial with boss 36 such that one spirally wound edge of the film ispositioned against the flat tray portion 40 of disk 38, and its otherspirally wound edge lies in a plane substantially parallel to andclosely adjacent to the inner wall of cover 14. By means of thispositioning, the spirally wound convolutions of the coil are preventedfrom being displaced axially of the roll relative to one another by anamount which might cause jamming of the filmstrip within the supplychamber 28. Lip 42 of disk 38 will overhang the marginal portion of theradially outer convolution of the coiled film 44 and normally preventthe outermost flat surface thereof from excessively engaging theperipheral wall of supply chamber 28 during rotation of the film roll.Similarly hub 145 will prevent the innermost convolutions of roll 44from crushing, collapsing, passing into opening 164 of the cartridge, orcinching around boss 36, any of which would restrict free rotation ofthe coreless roll of film as the film is withdrawn from supply chamber28.

The anit-friction disk 38, as disclosed, substantially confines the filmroll 44 and isolates it from direct engagement with all the stationaryparts of the supply chamber except the cover. The outer convolution ofthe film is restrained from clockspringing by lip 42 and hub 145prevents radially inward displacement of the inner convolution of film.Thus the anti-friction disk prevents the film from being displaced in anundesirable manner and thereby subjected to a frictional drag whichwould impede the film claw from readily pulling film from the supplyroll.

While the invention has been particularly described with reference tothe film cartridge, the invention also is applicable to other flexiblestrip handling cartridges, such as a tape supply for recorder and/orplayback device, wherein a web is moved from the supply chamber to atake-up means. v

The invention has been described in detail with particular reference toa preferred embodiment thereof, but it will be understood thatvariations and modifications can be effected within the spirit and scopeof the invention.

I claim:

1. In a cartridge having means defining a supply chamber, the chamberdefining means comprising first and second spaced walls, a stationaryboss projecting from said first wall toward said second wall, the outersurface of said stationary boss having a substantially cylindricalportion near said first wall and a frusto-conical portion near saidsecond wall with the smaller portion of said frusto-conical portionbeing adjacent said second wall, said cylindrical and frusto-conicalportions having an opening extending along a portion of said stationaryboss, said chamber defining means further comprising a rotatable memberpositionable in the chamber and having disk and hub portions forreceiving a supply coil of highly flexible strip material that cancollapse radially inwardly, said rotatable member and said coil beingdisposed substantially coaxially with said stationary boss and beingrotatable thereabout, said disk portion of said rotatable memberpositioned adjacent to said first wall and being between said first andsecond walls, and said hub portion of said rotatable member projectingfrom the disk portion substantially to said second wall and adapted tobe received inside the inner convolution of said supply roll, theimprovement comprising:

a separate reinforcing ring secured to said hub portion adjacent saidsecond wall and bridging said opening for supporting said coil andavoiding collapsing or cinching of said coil onto said stationary bossand into the area of the opening in said stationary boss, said ringextending radially inward from said hub portion toward saidfrusto-conical portion of said stationary boss, the inner diameter ofthe ring being smaller than the diameter of said clyindrical portion ofsaid stationary boss but larger in diameter than said frusto-conicalportion of said stationary boss that is located radially inwardly of thering.

2. in a cartridge for receiving a supply coil of highly flexible stripmaterial, the combination comprising:

first and second spaced walls partially defining a supply chamber;

a stationary boss projecting from said first wall toward said secondwall, said stationary boss having a substantially cylindrical portionnear said first wall and a frusto-conical portion near said second wall,said cylindrical and frusto-conical portions having an opening extendingalong a portion of said stationary boss such that when said supply coilis received in said supply chamber the coil tends to collapse or cinchin the area of the opening;

rotatable means positioned in said supply chamber,

said rotatable means comprising disk and hub portions for receiving saidsupply coil, said disk portion being disposed adjacent to said firstwall substantially coaxially with said stationary boss and rotatablethereabout, said hub portion projecting from said disk portionsubstantially to said second wall and'adapted to be received inside theinner convolution of said supply roll whereby the inner convolutions ofsaid coil are restrained from collapsing radially inward ontosaidstationary boss; and

a substantially rigid rim projecting inwardly from said hub portion toavoid radially inward displacement of said supply coil.

3. In a cartridge as set forth in claim 2 wherein said rim comprises aseparate reinforcing member attached to said hub portion remote from thedisk portion, thereby enhancing the resistance of the hub portion tobeing crushed by impact forces.

4. in a cartridge as set forth in claim 3 wherein saidreinforcing-member comprises a circular member seinwardly of saidcircularmember.

* i i i i

1. In a cartridge having means defining a supply chamber, the chamberdefining means comprising first and second spaced walls, a stationaryboss projecting from said first wall toward said second wall, the outersurface of said stationary boss having a substantially cylindricalportion near said first wall and a frusto-conical portion near saidsecond wall with the smaller portion of said frusto-conical portionbeing adjacent said second wall, said cylindrical and frusto-conicalportions having an opening extending along a portion of said stationaryboss, said chamber defining means further comprising a rotatable memberpositionable in the chamber and having disk and hub portions forreceiving a supply coil of highly flexible strip material that cancollapse radially inwardly, said rotatable member and said coil beingdisposed substantially coaxially with said stationary boss and beingrotatable thereabout, said disk portion of said rotatable memberpositioned adjacent to said first wall and being between said first andsecond walls, and said hub portion of said rotatable member projectingfrom the disk portion substantially to said second wall and adapted tobe received inside the inner convolution of said supply roll, theimprovement comprising: a separate reinforcing ring secured to said hubportion adjacent said second wall and bridging said opening forsupporting said coil and avoiding collapsing or cinching of said coilonto said stationary boss and into the area of the opening in saidstationary boss, said ring extending radially inward from said hubportion toward said frusto-conical portion of said stationary boss, theinner diameter of the ring being smaller than the diameter of saidclyindrical portion of said stationary boss but larger in diameter thansaid frusto-conical portion of said stationary boss that is locatedradially inwardly of the ring.
 2. In a cartridge for receiving a supplycoil of highly flexible strip material, the combination comprising:first and second spaced walls partially defining a supply chamber; astationary boss projecting from said first wall toward said second wall,said stationary boss having a substantially cylindrical portion nearsaid first wall and a frusto-conical portion near said second wall, saidcylindrical and frusto-conical portions having an opening extendingalong a portion of said stationary boss such that when said supply coilis received in said supply chamber the coil tends to collapse or cinchin the area of the opening; rotatable means positioned in said supplychamber, said rotatable means comprising disk and hub portions forreceiving said supply coiL, said disk portion being disposed adjacent tosaid first wall substantially coaxially with said stationary boss androtatable thereabout, said hub portion projecting from said disk portionsubstantially to said second wall and adapted to be received inside theinner convolution of said supply roll whereby the inner convolutions ofsaid coil are restrained from collapsing radially inward onto saidstationary boss; and a substantially rigid rim projecting inwardly fromsaid hub portion to avoid radially inward displacement of said supplycoil.
 3. In a cartridge as set forth in claim 2 wherein said rimcomprises a separate reinforcing member attached to said hub portionremote from the disk portion, thereby enhancing the resistance of thehub portion to being crushed by impact forces.
 4. In a cartridge as setforth in claim 3 wherein said reinforcing member comprises a circularmember secured to said hub portion.
 5. In a cartridge as set forth inclaim 4 wherein the inner diameter of said circular member is smallerthan the diameter of said cylindrical portion of said stationary bossbut larger in diameter than said frusto-conical portion of saidstationary boss that is located radially inwardly of said circularmember.